His Bestfriend, His Worst Enemy or Him!
by MysticAngel1864
Summary: Tessa has been feeling drawn to Gabriel Lightwood. How far will Will go to win Tessa's Heart back! Not only does Will have to worry about Jem but now he has to look out for Gabriel Too!
1. Chapter 1

**Now the Infernal Devices is set in Britain. London, England to be exact so try reading the story with a British Accent! There may be a few parts where in American English it seems weird and just plain stupid but like I said, it's supposed to be read in a British accent! **

**Chapter 1: Tessa POV:**

"Tessa, Sophie? We will be taking up Benedict Lightwoods offer on having his sons train you. I have left your training gear on your beds. Please immediately after breakfast, head up to the training room to meet the Lightwoods" Charlotte said in her most strict demeanor.

After the clave meeting Benedict Lightwood made a scene in front of the Consul saying that he should be the head of the London Institute. So now they have a deal. We have 2 weeks to find or get some serious info about Mortmain and if we don't, by the deadline Benedict will take over. But in the meantime, since Mortmain appeared at the institute and killed 2 of our helpers, the Lightwood children will be coming to train us and bring us new "replacements" as Benedict put it. One which wouldn't stop singing these horrible Irish ballads!

I was half way up the stairs towards the training room when Gabriel Lightwood came out, shutting the door behind him. Once he saw me a small smile grew across his acne free face. That was another thing about Shadowhunters that I really despised, they were born beautiful. As half human – half angel, they definitely got their beauty from the heavens. Though, I believe Will is 95% angel. It's not because his beauty is out of the world (though that's partly true), it's also because no matter how hard he gets hit or how serious his injuries are, he never dies, never…well I don't know. But if you ever wonder if angels truly have children, well here's a subject for you to observe.

Gabriel came up to me and laid his left hand on my shoulder and his right hand on me forehead, caressing my face and hair. I didn't know what to do, I knew Gabriel didn't have any affection towards me and was only doing this to get at Will. And it was working too because from all the way down the hall I could hear Will growling low in his voice at Gabriel's hand on my hair. In three great strides Will was at my side pulling me free from Gabriel's hands. "Come Tessa, Jem and I will train you instead of this bloody tit" he spat. He pulled me along the hall glaring at Gabriel until we turned a corner into the hallway that held Will's bedroom. He yanked the door open and pushed me inside slamming it behind him.

I sat on his bed in silence while Will leaned against the windowsill and stalked the various streetcars driving by. "Will, I..." but my words were left in the wind when Jem came into the room and whispered something into Will's ear.

"I've spoken to Charlotte, Gideon will continue to train Sophie however when it comes to Gabriel…."

"Yes, well what is it? Don't just stand there like a blob of smashed apricots, tell us?"

"Charlotte says that Gabriel will continue to train Tessa and we are allowed to accompany him."

"What! I'm not accompanying that twit! The only thing that I will be accompanying him to is his Coffin, where I will leave him in to rot his everlasting life in underground, where no one will be able to hear his horrible screeches. Oh! Those will be the days!"

"WILL!" Jem and I yelled! That baboon! One day Karma will come back and bite him in the behind for saying such nasty things. Plus, Gabriel isn't all that bad.

"I don't know why you bother. Gabriel's not that bad! He's sweet and tough and what any girl would want in a guy." I didn't realize that I had spoken aloud until Jem and Will's eyes were pinned on me like daggers and its target.

**WILL'S POV!**

I couldn't believe Tessa just said that! Gabriel? Charming?! You've got to be kidding me! He's as charming as a donkey! I swear sometimes I believe Tess has lost her mind. Charming, charming my behind!

**Jem's POV!**

Oh my sweet Tessa always wants to see the good in people! But haven't you noticed that Gabriel isn't the least bit kind. He would never fall for any girl unless it was his own mother. Even then we all still wouldn't know. The man is as nice and kind as a Porcupine.

**Tessa's POV!**

Why were they both staring at me! "Stop staring at me! It's creeping me out!" Jem stopped staring but t=instead of stopping, Will only continue on, widening the pupils by each passing second. Then all of a sudden, he started to break out dancing a singing in an offbeat pitch:

"_Oh he's charming, charming, charming as a donkey._

_Charming, charming, charming as the viper snake_

_But if you look more closely, you'll see what I see!_

_A little mad slut'in boy who doesn't know how to pee! Oh!_

_Now listen closely to what I have to say,_

_Gabriel, oh Gabriel he doesn't understand!_

_That the only way to be so stiff and mad_

_Is if he was a mad little slut'in boy!"_

WILL! SHUT UP!" Jem and I screamed!

"What in the racket is going on in here? Will why on earth are you standing on a chair like an ape, Jem, Tessa, what is going on here?" Charlotte screamed, coming in to the room.

"Tessa, aren't you supposed to be upstairs with Sophie, Gabriel and Gideon?" She asked.

"Oh yes of course! I will go meet them right now!"

I scurried along the hallway and stairs to meet up with Sophia. However, when I got to the training room door, only Sophie and Gideon were in there. Gabriel was not. And Gideon was getting a little too cozy over there with Sophia.

From the creak in the door, I could make out Gideon pinning Sophia to the wall while showing her how to use a dagger properly. Although, his hands were getting a little too low there on her back! Oh how dare he abuse her trust like that!

**Tessa seems to be working up a little affection for Gabriel! And Sophie and Gideon! If Tessa has her eyes on Gabriel, how in the world can William get her now? Do I smell Jealousy in the air? Well I hope you liked it! T's my first fan fiction story for anything Cassandra Clare! PLS, PLS REVIEW! **


	2. Chapter 2

**CHAPTER 2: TESSA'S POV:**

The days past by vigorously with the usual training sessions with Gabriel, secret visits from Jem and midnight clips of a drunk'in Will Herondale. It was Thursday, just past midnight when a rap came upon the door. William was leaning against the door frame smelling like cheap alcohol that was bought at the local apothecary.

"Will, bloody hell! What're you doing here?" I said astonished.

"Tess, I need to talk with you. It's about Jem…" he slurred.

"No Will, I've heard you time and again. I love Jem and that's final. We're getting married. Please understand!"

"Tess please, I love you! Jem will understand!"

"Your drunk! GO BACK TO BED!" I screamed, slamming the door in his face.

Slumping on my bed, I opened the copy 'The Shadowhunter's Codex' that Will had given me. I was starting the section about warlocks when he interrupted. Looking back on the page it says that Warlocks cannot have children at all. What about my family? The family that I've been wanting since I've been an infant. But most importantly, how was I born? Magnus and the others are saying that I'm a warlock or at least half. But that's not possible. Both of my parents are mortal, aren't they? Nowhere in my memory have I seen any unknown or extra-terrestrial like event happening in my past. So how do you explain it? A knock then came upon my door. Oh God! Not Will again!

"Hello?" I opened up the door to find Jem. "JEM!" I yelled running into his arms.

"Tessa! What the…?" He enveloped me into his arms and squeezed me tight.

"I've missed you!" He had been out with Henry gathering information about Mortmain.

"I've missed you too." Jem pulled me in closer and we shared a short passionate kiss. His lips were soft like a feather and he tasted like strawberries. His hands slid around my waist and we carefully, without breaking the kiss, started to maneuver around the bed and on the small sofa in my room. We sat there, entwined in each other's warmth and enjoyed the bliss. When we broke apart, Jem had worry written all over his face.

"What's wrong Jem? Did I do something wrong?"

"NO! It's not you, it's Will. He's been acting strange lately and for some reason wouldn't talk with me like we did before? Have you any clue what's going on?"

"No, I'm sorry Jem. I don't really know. But he's your blood brother, and you've both gone through so much together. He'll come around soon." I hated lying to him. Will hates that were getting married. He's not talking with Jem because he doesn't want to hurt his feelings and the best way to do that is to stop talking to him in total.

"Thanks Tessa! You're amazing you know that?" He gave me a soft kiss and quickly left the room.

"Oh, why did you have to say that?" I quietly left my room and krept down the hall towards Will's. When I opened the door he was a sleep on his futon snoring away. I decided to come back later or catch him after dinner.

A few hours later we were all getting ready for dinner. The food was about to get served when there was someone at the door. Cyril came in to introduce a young teenage girl with long blondish brown hair and blue eyes. She was dressed in a casual green dress and carried two black suitcases with her.

"Hello, My name is Cecily Herondale and I would like to ask for safety upon the Institute."

Cecily? As in Will's little sister?

"Cecily?" Will asked surprised.

"Brother!" The young girl through her body into Will's arms and cried her yes out. "Big Brother! I've found you at last!"

"Shh! It's alright Cecily. Why are you here to stay? Go home to mom and dad!"

"But I can't! Don't you see! Mom and dad are….dead!"


	3. Chapter 3

**CHAPTER 3: Will's POV:**

"DEAD!" I yelled astonished. How could this be? Just two days ago Tessa, Jem and I had seen them together getting out of the carriage. "How could they be dead?" I rushed over to her, grabbed her by the shoulders and shook her senseless. "HOW?!"

"Will! That's enough!" Jem had me by the waist and was trying his hardest to wrench me away from Cecily.

"Stop it Will!" Tessa yelled. It was pointless to argue. Whenever Tess told me to stop, the side of me who loved her automatically gave in.

"H-h-how? Cecily how did t-t-this happen?"

"It all came in a rush Will! First, we were sitting down eating dinner and the next thing we knew, there were these giant mechanical like people surrounding us. They killed mom and dad in front of me, Will! It was just…HORRIBLE!" She rushed into Tessa's arms and cried her eyes out.

**Tessa's POV:**

It was awful what happened to Will's family but even more when they made Cecily watch her parents die. There is no doubt in the world that this was Mortmain's doing. He's the only one that can both create and control those clockwork creatures.

"Tessa, why don't you take Cecily to her new room? Now that Jessamine is gone, she can have her room." Charlotte said.

"Oh, alright. This way Cecily, please." I lead Will's sister down the long corridor and through the hallway that held all of our rooms. Jessamine's or now Cecily's room is just next to mine and across from Jem's. "Will's room is just down the hall there on the right. He likes his peace and quiet so he asked for that room." I told her. We walked into the room and placed her things onto the bed. Cecily walked toward the window and sat in the light blue love seat. She never spoke or showed any sign of life after that. "I will just leave you now. Sophie will be here later on to help you get ready for bed. Breakfast starts at eight. Well, goodnight."

I left Cecily to her own demise and headed for my own room. I could understand why she would be depressed but, how could Will get angry at her for something she couldn't help? Sometimes I just don't understand boys. I was walking down the corridor when I heard the sweet sound of music coming from Jem's room. I'm glad he's still playing. He's doubted his talent since the day Will got drunk on his "medicine".

"Jem?" I said peeing into the room. Jem was on his bed and Will was leaning against the windowsill. "Oh! I didn't know you were busy. I'll talk with you later". I was just about to walk away when someone placed a hand on my shoulder. I turned around and found Will behind me.

"How is she?" he said.

"She's fine. But if you would like to see for yourself, she's staying in Jessamine's old room."

"NO!" he yelled and quickly backed away. "I mean… I don't want to disturb her. She's probably sleeping. And so should all of us. Well, goodnight Jem, Tess". Will hurried down the hall and and practically threw himself in his room.

"Good night Will!" Jem and I yelled down the hall.

"Well, goodnight Jem. Sweet dreams".

"Wait, Tessa. I want to talk with you for a second".

"Um… alright".

"How do you feel about…um… well…?"

"How do I feel about what? Jem?"

"Um well…Us?"

"Us? Well, What do you mean?"

"Well, I see how you look at Will. And I can understand. I mean, he did save you from those warlock sisters. But feeling wise, who are you with?"

What was I supposed to say? The truth? The truth was I loved Will. I love him as the air I breath but… every time I try to get close he pushed me away. One minute he likes me and then the next minute I disgust him. But with Jem, I admit I have feelings or him and he does appreciate my live, my soul. An mot importantly, we can have a live together. _What am I going to do?_


	4. Chapter 4

**CHAPTER 4: TESSA'S POV:**

Who was I with, feelings wise?

Truth be told, even though it's nowhere close to it in reality, I'm with Will. But how could I tell Jem that? Jem was willing to sacrifice his whole life to be with me. He's supposed to be a shadowhunter like Will and his parents but instead he wants to leave that and run away with me. After confessing that to me and proposing, how in the world am I supposed to tell him that my heart truly lies with his blood brother? The last thing I would want to do is break his heart.

"Tessa, I know you love Will."

"What? No! Jem!" I said exasperated.

"Don't. I…I know. But I want to know if you love me and are willing to be with me; willing to let time bring us closer together."

"Jem…I…" I was cut off by a swift knock on the door. Will didn't even wait for either of us to open the door to come in.

"Oh…I didn't know. I wanted to speak with you Jem…but I guess it could wait until later.

Will left to his room without another word. It was his usual behavior however; something was off by the way he spoke. He seemed…worried and unsettled so to speak. Jem and I were extremely concerned. One thing Will was famous for was keeping his emotions and mind to himself and when let others see into him…it wasn't good. He _never_ lets anyone see into him. Sometimes he lets Jem and me but only once in a blue moon.

"I'm sorry Tessa but can we continue this conversation tomorrow? Will needs me."

"Oh, Yes of course. Good night Jem." I left the room returning to my own. There was only one thing that could make Will act like this. It was his sister Cecily. Jem and I didn't know much of it. Actually, I believe only the Clave and Charlotte knew about his family. Will doesn't like anyone knowing about his past.

-THE NEXT DAY-

Sophie woke me up in the morning saying that breakfast would be an hour later since Charlotte and Henry were still gone. They had left early in the morning for the doctors to see how the baby was doing. I decided to take the free time as a break from all the training and ventured to the library. The library was my favourite place of all times. It was where I could think freely and could answer any troublesome questions that haunt me in my every waking hour. There as nothing new about the library. There was only old or ancient materials; my favorite thing about the library. In the bookcases there were Shakespeare, Dickens, Twist, Grim Brothers, everything old classic. I understand why. With all the deaths and sadness that the shadowhunters bring in with them, they might just need a little old and a little classic.

I ventured to my favorite case which held all the Dickens Novels. My favorite was The Tales of Two Cities. I don't know why but there's just something about Dickens that draws me to his writings. I was just about to grab the phenomenal book when a loud rap came from the door.

"Hey Tessie" Will said.

"Will? Um… what're you doing here? I thought you'd be sleeping in or with Cecily?"

"No, I actually wanted to speak with you." Oh god no! Every time Will talks to me we always end up either kissing or about to kiss.

"It's about you and Jem. You see I know what I said earlier but… well, I love you Tessa. I love you and as much as I love Jem I just can't let him take you."

"Will! No, you can't! Jem and I are engaged to get married! You can't just blurt this out now! You had all the time in the world to tell me this before but not now!"

"Tessa, don't act like you don't love me back. You love me, not Jem. Admit it. I see the way you're with him. It's not love. Its affection towards a friend but not a lover."

"He's right. You don't love me…" A voice said from behind the doorway.

"Jem… I-" I cdidnt know what to say. How could I say something like that to him. It's Jem.

"And I don't love you." He continued.

"What!" Will and I said at the same time.

"Don't get me wrong. I love you but not the same way you and Will love each other. You two belong with one another. I guess… I guess I'm just the third wheel, the friend."

"Oh, Jem, no! You're not the third wheel. We're all friends here even if Tessa and I are in love. Plus we'll help you get a girl too."

"What Will means is that one of these days, You will find someone special. Don't worry."

**What is in stored for the three best friends? Now that Will and Tessa are free to be with one another, what will lie ahead of them? What has happened with Charlotte and her baby? Stay tuned for the next chapter of ****HIS BESTFRIEND, HIS WORST ENEMY OR HIM?**


	5. Chapter 5

**Chapter 5: Tessa's POV:**

"Will, I feel bad for Jem."

"Tessa…Jem said he was fine with us being together. And I know Jem; he'll find someone pretty soon."

"I know but still…" Will cut me off, kissing me on the lips.

"Enough. Let's go to my room. I have to show you something."

We walked down the narrow hallway and just as we were about to enter his room, Gabriel showed up.

'Ah, Tessa. There you are. I was looking all over for you."

**Will's POV:**

Oh great. Not him! What does he want with my precious Tessa.

"Tessa, my dear. I thought we'd continue with our lessons. Shall we?" Gabriel said,

"That's alright. I'll teach her new tricks later. Right now were busy. Go away!" I said.

"Oh, Will. Sorry I didn't see you there. Why are you here again? Oh yes, that's right. You ran away from home! Daddy, didn't love you anymore?" Gabriel said in a baby voice.

That's it! He has gone too far! Before I could even cross the room, I heard this loud _**Slap!**_ Tessa had slapped Gabriel across the face. It must have been hard to cause a red hand print was easily visible against his pale white skin.

"How dare you! I knew you two hated each other, but that was just too cruel! You're despicable Gabriel! Come on Will." Tessa took my hand and we went into my room. I knew it hurt Tessa to have done that even before I looked at her. That was one reason why I knew we belonged together. We knew each other without words, actions or any other silly means of communication. It was just there in our minds and hearts. I rushed over to where she was sitting on my bed and wrapped her in my arms. She was warm. Her skin was so smooth and she was wearing a simple blue silk dress.

My room was like any other room in the institute. There were four black walls, one window sill and a bookshelf sitting beside the window. All five shelves were filled with classics like _The Tales of Two Cities_, _Oliver Twist, _and _The Count of Monte Cristo._ My single bed sat in the middle of the room with a black wooden chest in front of it. In there, I held all of my darkest secrets. One day in which I intend to show Tessa, I she'll have me that long.

**Tessa's POV:**

It felt good to be in his arms. Will might be lonely and broken on the outside, but I could feel that there is only love in his heart. I could have been in those strong arms for hours had he not disturbed the blissful moment.

"I know it's your favourite. How about we lie down and read it together?" Will took out _The Tales of Two Cities_ from his bookshelf and lay down with me on the bed. He pulled me into his arms and we lay there together reading my all-time favourite book. For most girls, I walk in the park during a starry sky would have been the perfect moment. But, not for me. _This_ was the perfect moment and I never wanted it to end.

**Jem's POV:**

"I had to do it. I knew how much they loved each other. Will and Tessa belong together. I should never have gotten in between them."

"Who are you talking to?" a soft voice said behind me. I turned around to see Will's little sister Cecily watching me with her childish eyes.

"Oh, my apologies Ms. I didn't see you there." I bowed to show my respect. After all the Herondales are a Shadowhunter family.

"You're James, am I right?" She spoke in that beautiful tone again. It was like a soft violin; soothing and comforting.

"Yes, you are correct. However, some call me Jem."

I couldn't help but be shy with her. She seemed so fragile and sad. Instinct had me wanting to rush over to her and hold her in my arms. However, my conscious had me stay put. She may be fragile but she is also a Shadowhunter by blood. And it would be incredibly rude to do so. Without saying anther word, Cecily strode past me and went to her room which just happened to be down the hall from Tessa and mine.

Why was I so drawn to her? Technically, if you count the scene when she first came to us, this would be our second meeting. Every time I see her a part of me is over come with utter joy. Why? Why does my heart flutter every time I think of her?

**Hey guys, I hope you like this little gushy chapter. Will and Tessa! Yay! So what do you guys think about Jem and Cecily? Will they be a couple or would this feeling just be a simple little crush? Stay tuned for more! And remember: **_**When in doubt – R&R!**_


	6. Chapter 6

**Chapter 6: Tessa's POV:**

I woke up and I was surrounded by warmth. I looked around and I realized I wasn't in my own room. I was in Will's room and he was sleeping right beside me. His arms were around me and that soft fluffiness I thought was a pillow was actually Will's shoulder holding me and his golden blond hair falling onto my face. _A Tale of Two Cities _was lying half open on the nightstand alongside his stele and witchlight. And so was a copy of the Shadowhunter Codex he had given to me earlier. Will must have gotten it from my room when I was asleep. I could still see the little slip of paper I used to mark my page. I remember I was reading the section on downworlder's especially Warlocks. Magnus Bane said that if I was a warlock I would have a distinctive part of me be… well, un-human. He said some warlocks have elf ears, webby wings and stuff like that. The only problem with me is that I have the powers of a warlock but no warlock mark.

I turned the light on, making sure I don't wake up Will and opened the book to the page I left off on.

_ Warlocks are not capable of bearing children considering they are an offspring of a demon. Demon blood disables warlocks from fertility considering the acid and dangerous fluid in their systems would kill any enfant. As a result, if warlocks are capable of giving birth, most likely the child would be born dead or die after a few minutes from birth. _

So it's true, I can't have children. But… what about Will? What if he wants to have children? If I can't bear his children, what then? And what about me? Magnus said that in order for me to be a warlock, I would have to have had a downworld parent. I already knew my mother was a shadowhunter, who's my father? _What_ is my father?

"Mhmmm" Will stirred from where he slept beside me. "Too bright Tessa. Turn the light off and come closer. I can't sleep properly when your close but not in my arms." He said with his eyes shut.

"I'm reading up on warlocks. I'll be there in a minute. I want to know more on who my birth father was? Maybe the codex can help me?"

"Later, Tess." With his eyes still shut he reached over and plucked the book out of my hands. Before I can make a sound he crushes his lips against mine and with his other hand, turns off the bedside lamp. "Has any one ever told you that you read too much?"

"No, never in my life"

"Well then I glad to be the first"

I snuggled up close to him letting Will rap his arms around me and pull me close. It always felt nice to be around him. Even if he's a total jerk all the time, it's still always nice. He has this homey sense to him. Safe and at peace is how I always feel when I'm close to him. Yes, he's annoying and immature at times but like they say opposites attract right? Will has that sense of bravery and we can't help but think "what next" but with Jem… He's predictable. He's the silent but fierce type. When he's around you can predict what he'll do. He has no edge to im like Will. I love Jem, I really do but… I'm not in love with his as I am with Will. Will… he's my other half, my soul, my heart. I know now that I wouldn't be able to survive without him, no matter what.

"What are you thinking, my love" Will whispered in my ear.

"About you"

"Can't get enough of me during the day so now your dreaming about me?" Will said witfully.

"Mhmmm. You make it sound like it was a happy dream. Maybe I was having a nightmare."

"Impossible! For many years I have only been in women's dreams. No nightmares! None what so ever!"

"It's a first time for everything"

"Your right. And if memory serves me correctly I believe we haven't done a certain something at all since we've been together"

"A certain something?" What could he be talking… "Oh" That.

"Mhmm-Hm"

He pulled me closer and nuzzled my neck. He slowly traced small kisses up and down my neck while undoing the buttons on the cotton shirt he had let me borrow. His soft hands trailed up and down my legs massaging my skin. I couldn't help the moan that escaped my throat. He knew how to woe me.

We made passionate love to one another for what felt like hours. My body and his fit together like the sun and day. I laid there in his warm muscular arms while he continued to plant kisses all over my body never letting go of me for one second. The hole time during our love I felt our bond. The bond that united us and brought us together since the very beginning. We belong together. William Herondale is my soul mate.


End file.
